Application of MnPSe3 nanoparticles in improving salt stress resistance of plants

Abstract

The invention relates to the field of cultivation and planting of commercial crops, in particular to application of MnPSe3 nanoparticles to improvement of salt stress resistance of plants. MnPSe3 nanoparticles and water are uniformly mixed to prepare a nano solution, and then the nano solution is sprayed on the surfaces of plant leaves. When the MnPSe3 nanoparticles are applied to mesembryanthemum crystallinum leaves in a salt stress environment, the salt stress of the mesembryanthemum crystallinum can be remarkably relieved, and meanwhile, the oxidation resistance and the anti-sugar activity of the mesembryanthemum crystallinum can be enhanced. The method provided by the invention not only improves the yield of mesembryanthemum crystallinum under salt stress, but also improves the alpha-amylase inhibitory activity of the mesembryanthemum crystallinum.

Description

Technical Field

[0001] The invention relates to the field of economic crop cultivation and planting, and in particular to the application of MnPSe3 nanoparticles in improving plant resistance to salt stress. Background Art

[0002] The formation of saline-alkali land is mainly the result of the combined effects of natural factors and human activities. Natural factors include rainfall less than evaporation, high groundwater level, high salt content of soil parent material, etc. Human factors such as excessive irrigation, unreasonable land use, and poor drainage can also aggravate salinization. Saline-alkali land has a serious impact on agricultural production and the ecological environment, resulting in reduced crop yields or even failure to grow, destroying the balance of the ecosystem, and affecting biodiversity.

[0003] Saline-alkali land causes multiple hazards to vegetable growth. First, high salt content increases the osmotic pressure of the soil solution, making it difficult for vegetable roots to absorb water, and even causing water backflow, causing vegetable dehydration and physiological drought. Second, excessive sodium and chloride ions are toxic, interfering with the activity of enzymes in vegetable cells, affecting the absorption and metabolism of nutrients, leading to leaf burns and growth stunting. In addition, the high salt content in saline-alkali land will also change the soil structure, causing the soil to become compacted, and the air permeability and water permeability to deteriorate, further affecting the growth and development of the root system. These factors work together to severely restrict the growth and development of vegetables, reduce crop yields and quality, and even cause vegetable death, posing a major challenge to agricultural production.

[0004] Ice vegetable is a vegetable with both nutritional and medicinal value. From a nutritional point of view, it is rich in vitamin C, vitamin A and dietary fiber, which helps to enhance immunity, promote digestion and maintain skin health. It also contains important minerals such as calcium, iron and potassium. In terms of medicinal use, ice vegetable has the effects of clearing away heat and detoxifying, diuresis and swelling, and can be used to relieve febrile diseases such as fever and sore throat. In addition, its active ingredients help delay aging and lower blood sugar, making it a functional vegetable with high nutritional value. However, saline-alkali land significantly affects the growth of ice vegetable due to high salt and alkaline substances, making it difficult for the roots to absorb water and nutrients. At the same time, it changes the properties of the soil, inhibits the absorption of trace elements by ice vegetable, causes physiological diseases, and ultimately greatly reduces yields.

[0005] Currently, the main methods to alleviate salt stress include soil improvement, irrigation management, and biotechnology, etc. Soil improvement reduces the soil salt content and improves the soil structure by applying organic fertilizers or chemical amendments; irrigation management adopts techniques such as drip irrigation or subsurface drip irrigation to reduce the accumulation of salts on the soil surface; biotechnology focuses on using salt-tolerant plants or genetic engineering means to cultivate salt-tolerant crop varieties and improve the adaptability of plants to salt stress. In recent years, due to their large specific surface area and high reaction activity, nanomaterials have shown unique advantages in alleviating salt stress. Nanomaterials can adsorb soil salts more efficiently, promote the absorption of nutrients by plant roots, and thus enhance the salt tolerance of plants. Therefore, in the face of the increasingly serious problem of saline-alkali land, nanotechnology, as a new solution, has received wide attention. Summary of the Invention

[0006] The object of the present invention is to provide an application of MnPSe3 nanoparticles in improving the salt stress resistance of plants. The present invention discloses a nanomaterial called MnPSe3, which is rich in manganese (Mn), phosphorus (P), and selenium (Se) elements beneficial to the growth of vegetables. Applying this nanomaterial to the leaves of ice plants under salt stress environment can significantly alleviate the salt stress of ice plants, and at the same time enhance their antioxidant capacity and anti-glycation activity. This method not only increases the yield of ice plants under salt stress, but also improves the α-amylase inhibitory activity of ice plants. By spraying nanoscale MnPSe3 on the leaves, the salt stress resistance and nutritional value of ice plant crops can be improved under saline-alkali land stress.

[0007] In order to achieve the above-mentioned invention object, the present invention provides the following technical solutions:

[0008] The present invention provides an application of MnPSe3 nanoparticles in improving the salt stress resistance of plants.

[0009] Preferably, the method of the application is:

[0010] Mix the MnPSe3 nanoparticles evenly with water to make a nano-solution, and then spray the nano-solution on the surface of plant leaves.

[0011] Preferably, the mass-volume ratio of the MnPSe3 nanoparticles to water is 50 - 150 mg / L.

[0012] Preferably, the spraying interval time is 4 - 7 days, and the spraying times are 1 - 2 times.

[0013] Preferably, the plant is ice plant.

[0014] The present invention also provides an application of the MnPSe3 nanoparticles in improving the antioxidant capacity of plants under salt stress. The application method is as follows: Dissolve the MnPSe3 nanoparticles to a concentration of 50-150 mg / L and then spray them on the surface of plant leaves.

[0015] The present invention also provides an application of the MnPSe3 nanoparticles in improving the anti-sugar activity of plants under salt stress. The application method is as follows: Dissolve the MnPSe3 nanoparticles to a concentration of 50-150 mg / L and then spray them on the surface of plant leaves.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] The present invention demonstrates that nano-MnPSe3 alleviates the damage of salt stress to ice plants and improves the anti-sugar activity of ice plants. By applying nano-MnPSe3 to ice plants under salt stress conditions, a significant improvement in the growth status of ice plants was observed, specifically manifested as an increase in leaf area and a decrease in the content of malondialdehyde and proline. The improvement of the above physiological indexes not only alleviates the adverse effects of salt stress on ice plants, but also enhances the anti-sugar ability of ice plants by inhibiting the activity of α-amylase, improving the nutritional and medicinal values of ice plants.

[0018] The preparation method of the MnPSe3 nano-solution described in the present invention is simple, the application process is convenient, and it is environmentally friendly, having broad application prospects and market potential. Description of the Drawings

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only the embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained according to the provided drawings without creative efforts.

[0020] Figure 1 It is a transmission electron microscope image of MnPSe3 nanoparticles, with a scale bar of 50 nm;

[0021] Figure 2 It is a growth schematic diagram of ice plants under different treatment conditions;

[0022] Figure 3Results graphs of leaf area, proline content, and malondialdehyde content; among them, A is the leaf area, B is the proline content; C is the malondialdehyde content; CK is the 0 mM NaCl treatment group, Salt is the 200 mM NaCl treatment group, Mn50 is the group treated with 50 mg / L MnPSe3 under 200 mM NaCl stress, Mn100 is the group treated with 100 mg / L MnPSe3 under 200 mM NaCl stress, and Mn150 is the group treated with 150 mg / L MnPSe3 under 200 mM NaCl stress;

[0023] Figure 4 Results graphs of photosynthetic indicators of plant leaves before and after nanomaterial treatment; among them, A is the photosynthetic efficiency; B is the intercellular CO2 concentration; C is the transpiration rate; CK is the 0 mM NaCl treatment group, Salt is the 200 mM NaCl treatment group, Mn50 is the group treated with 50 mg / L MnPSe3 under 200 mM NaCl stress, Mn100 is the group treated with 100 mg / L MnPSe3 under 200 mM NaCl stress, and Mn150 is the group treated with 150 mg / L MnPSe3 under 200 mM NaCl stress;

[0024] Figure 5 Confocal fluorescence imaging of superoxide anion, with a scale bar of 10 μm;

[0025] Figure 6 Confocal fluorescence imaging of hydrogen peroxide, with a scale bar of 10 μm;

[0026] Figure 7 Results graph of MnPSe3 nanoparticle metabolism, with a scale bar of 10 μm;

[0027] Figure 8 Results graphs of the detection of soluble sugar and soluble protein content; among them, A is the soluble sugar content; B is the soluble protein content;

[0028] Figure 9 Results graphs of the detection of the antioxidant activity of the crude extract of ice plant leaves under different treatments; among them, CK is the 0 mM NaCl treatment group, Salt is the 200 mM NaCl treatment group, Mn50 is the group treated with 50 mg / L MnPSe3 under 200 mM NaCl stress, Mn100 is the group treated with 100 mg / L MnPSe3 under 200 mM NaCl stress, and Mn150 is the group treated with 150 mg / L MnPSe3 under 200 mM NaCl stress;

[0029] Figure 10It is a graph showing the inhibitory effect of the crude extract of ice plant leaves under different treatments on α - amylase activity. Among them, CK is the 0 mM NaCl treatment group, Salt is the 200 mM NaCl treatment group, Mn50 is the treatment group with 50 mg / L MnPSe3 applied under 200 mM NaCl stress, Mn100 is the treatment group with 100 mg / L MnPSe3 applied under 200 mM NaCl stress, and Mn150 is the treatment group with 150 mg / L MnPSe3 applied under 200 mM NaCl stress. Detailed implementation manners

[0030] The technical solutions provided by the present invention will be described in detail below in conjunction with embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0031] The experimental methods in the following embodiments are all conventional methods unless otherwise specified. The materials, reagents, etc. used in the following embodiments can all be obtained from commercial channels unless otherwise specified.

[0032] The MnPSe3 (abbreviated as "NPs") nanoparticles in the following embodiments were purchased from Moke Nano (particle size 5 - 20 μm, purity ≥ 99.95%). The MnPSe3 crystals were dissolved in N - methyl - 2 - pyrrolidone solution (2 mg / mL), and ultrasonic crusher (600 W, ice bath for 24 h, 5 s on / 3 s off) was used for crushing, and then combined with gradient centrifugation. The large particles that were not crushed were removed at 4000 rpm, and the small particles were collected at 14000 rpm to obtain nanoparticles with a particle size of about 30 nm.

[0033] Example 1 Application of nano - MnPSe3 in improving the salt stress resistance of ice plant

[0034] 1. Planting of ice plant seedlings

[0035] Select ice plant seeds with uniform size and plump grains, place them in flower pots of 16 cm × 16 cm, and use a mixed substrate with a volume ratio of nutrient soil to perlite of 2:1. Plant them diagonally to ensure sufficient space. Cultivate in an environment of 23 °C and humidity of 45%, with 6 treatments in each group. Water regularly until the ice plant grows 3 pairs of leaves, and then perform salt treatment.

[0036] 2. Salt solution treatment

[0037] Prepare 200 mM NaCl solution, water the ice plant once a week, and irrigate the soil with water every two weeks to wash away the excess salt to maintain an appropriate salt concentration and prevent salt accumulation.

[0038] 3. Nano - solution treatment

[0039] Preparation of nano-solution: Weigh 50 mg, 100 mg, and 150 mg of MnPSe3 nanoparticles respectively, and use ultrasonic treatment at 180 W for 30 min at room temperature to ensure that the nanoparticles are evenly dispersed in ultrapure water, obtaining nano-solutions with concentrations of 50 mg / L, 100 mg / L, and 150 mg / L respectively. Figure 1 This is the transmission electron microscope image of nano-MnPSe3, indicating that the dispersion of nano-MnPSe3 is good, the particle size is uniform, the appearance is spherical, and the diameter is about 30 nm.

[0040] Application of nano-solution: Use a spray bottle to evenly spray on the leaves of Mesembryanthemum crystallinum twice a week, ensuring that each leaf surface is fully covered with the nano-solution for effective experiments.

[0041] 4. Experimental grouping

[0042] By spraying nano-particles with different concentrations, explore their effects on the growth of Mesembryanthemum crystallinum under salt stress, aiming to optimize the spraying concentration and improve the salt tolerance of Mesembryanthemum crystallinum. Divide the cultivated Mesembryanthemum crystallinum seedlings with consistent growth trends into 5 groups on average, with 6 seedlings in each group. The Mesembryanthemum crystallinum is first subjected to salt stress treatment for one week, and then the nano-solution is sprayed. The specific grouping methods are as follows:

[0043] Control group (CK group): Spray 0 mM NaCl + clear water;

[0044] Salt treatment group (Salt group): Spray 200 mM NaCl once a week, and pour clear water every four weeks to wash away the salt to prevent the accumulation of salt;

[0045] Salt + nano-solution treatment group:

[0046] Mn50: On the basis of salt treatment, spray 50 mg / L MnPSe3 nano-solution twice a week;

[0047] Mn100: On the basis of salt treatment, spray 100 mg / L MnPSe3 nano-solution twice a week. Mn150: On the basis of salt treatment, spray 150 mg / L MnPSe3 nano-solution twice a week;

[0048] After culturing for 30 days, take the first and second true leaves to measure various indicators.

[0049] 5. Determination of leaf area, proline content, and malondialdehyde content

[0050] (1) Determination of leaf area

[0051] Two weeks after the nano-material treatment, when significant differences in the growth of Mesembryanthemum crystallinum are observed, take photos of the leaves (see Figure 2 ), and use Image J software to measure the leaf area for quantitative analysis of the effects of different treatments on the growth of Mesembryanthemum crystallinum.

[0052] (2) Detection of proline and malondialdehyde content

[0053] Select 0.1 g of fresh leaves at the same leaf position of the plants under different treatments and place them in a mortar; then add 1.5 mL of 100 mM, pH = 7.8 PBS buffer (stock solutions of NaH2PO4 and Na2HPO4, PBS needs to be freshly prepared and stored at room temperature) for homogenization; the whole operation process is carried out on ice. Subsequently, centrifuge at 4 °C and 10,000 g for 20 min; after centrifugation, transfer the supernatant to a new centrifuge tube and place it on ice. The crude extract is prepared for subsequent determination of proline and malondialdehyde content. Finally, through the formula protein concentration (mg / mL) = 1.55×A 280 -0.76×A 260 Determine the concentration of the crude extract; the results show that the concentration of the CK group is 1.249 mg / mL, the Salt group is 1.328 mg / mL, the Mn50 group is 1.263 mg / mL, the Mn100 group is 1.177 mg / mL, and the Mn150 group is 1.230 mg / mL.

[0054] Determination of proline content: Prepare 100 mM PBS (PH = 7.0), 2.5% acidic ninhydrin, and 3% sulfosalicylic acid. Configure the working solution (10 mL of 3% sulfosalicylic acid, 10 mL of acetic acid, and 20 mL of 2.5% acidic ninhydrin). Prepare 1.5 mL centrifuge tubes, add 100 μL of the above crude extract to 1 mL of the working solution, and use 100 μL of 100 mM PBS (PH = 7.8) for the control group and add it to 1 mL of the working solution. Boil the mixture in a water bath for 15 min, and then cool the mixture on ice for 5 min. Take 200 μL of the mixture and measure the absorbance at 520 nm.

[0055] Determination of malondialdehyde content: Prepare 10% trichloroacetic acid (TCA) and 0.25% thiobarbituric acid (TBA). The working solution is 0.25% TBA. Prepare 1.5 mL centrifuge tubes, add 100 μL of the crude extract of ice plant under different treatments to 1 mL of the working solution. Use 100 μL of 100 mM PBS (PH = 7.8) for the control group and add it to 1 mL of the working solution. Boil the mixture in a water bath for 15 min, and then cool the mixture on ice for 5 min. Take 200 μL of the mixture and measure the absorbance at 532 nm and 600 nm.

[0056] The growth results of ice plant under different treatment conditions are as Figure 2 shown Figure 2It is a schematic diagram of the growth of ice plants under five different treatment conditions. It can be seen that the ice plant plants under salt stress show an obvious phenotype of being weak and small; after spraying the nanomaterial, the growth of the ice plant plants gradually approaches that of the control group, and when the concentration of the nanosolution is 100 mg / L, the growth of the ice plants is the best. When the spraying concentration of MnPSe3 is 150 mg / L, the leaves curl, indicating an excessive spraying of the nanomaterial.

[0057] The results of the determination of leaf area, proline content, and malondialdehyde content are as Figure 3 shown. When ice plants are under salt stress, the plants grow short, the plants undergo oxidative stress, the content of malondialdehyde, as an oxidative stress marker, increases significantly, and proline plays a role in maintaining water balance and its content increases significantly. The leaf area of ice plants is the largest compared to salt stress when the nanosolution is 100 mg / L ( Figure 3 A), the proline content is the lowest when the nanosolution is 100 mg / L ( Figure 3 B), and the malondialdehyde content is also the lowest under the 100 mg / L treatment ( Figure 3 C); the above results show that spraying the nanomaterial has a significant effect, and the optimal concentration is 100 mg / L. However, when the concentration is too high, it may have an inhibitory effect. After plants are under salt stress, they undergo oxidative stress and produce superoxide anions (O 2- ).

[0058] 6. Measurement of photosynthetic indicators

[0059] Use a plant photosynthesis meter to measure the photosynthetic efficiency, transpiration rate, and intercellular CO2 concentration of plant leaves. The results are as Figure 4 shown, where Figure 4 A is the change in photosynthetic efficiency before and after treatment with the nanomaterial. It can be seen that the photosynthetic efficiency of plants decreases significantly after being under salt stress and is alleviated after spraying the 50 mg / L and 150 mg / L nanosolutions; Figure 4 B is the change in intercellular CO2 concentration before and after treatment with the nanomaterial. It can be seen that the intercellular CO2 concentration of plants increases significantly after being under salt stress and is alleviated after spraying the nanosolution; Figure 4 C is the change in transpiration rate before and after treatment with the nanomaterial. It can be seen that the transpiration rate of plants decreases significantly after being under salt stress and is alleviated after spraying the nanosolution.

[0060] 7. In vivo imaging of reactive oxygen species

[0061] After two weeks of ice plant treatment, small round pieces with a diameter of 5 mm were taken from the first and second true leaves respectively. After pricking 3 - 5 small holes with sharp tweezers, they were incubated in 25 μM of 2’,7’-Dichlorodihydrofluorescein Diacetate (H2DCFDA) and 10 μM of Dihydroethidium (DHE) respectively. After incubation for 30 min, the round pieces were rinsed 3 times with TES buffer, placed face up on a glass slide, and pressed. A Leica SP8 laser confocal scanning microscope was used to image the samples.

[0062] The results are as Figure 5 shown. After plants are subjected to salt stress, oxidative stress occurs and superoxide anions (O 2- ) are produced. Figure 5 Figure is the confocal fluorescence imaging of superoxide anions. DHE can stain superoxide anions in the leaves to show green fluorescence; the autofluorescence of chloroplasts is red fluorescence; the combination of the two can localize and quantify the content of superoxide anions. It can be seen from the figure that the fluorescence content in the 200 mM NaCl treatment group is significantly greater than that in the watering control group, and the fluorescence content detected in the ice plant leaves treated with 100 mg / L of the nano-solution is less than that in the 200 mM NaCl treatment group, indicating that spraying 100 mg / L of MnPSe3 nano-solution under salt stress reduces the content of O 2- in the leaves.

[0063] The results are as Figure 6 shown. After plants are subjected to salt stress, oxidative stress occurs and hydrogen peroxide (H2O2) is produced. Figure 6 Figure is the confocal fluorescence imaging of hydrogen peroxide. H2DCFDA can stain hydrogen peroxide in the leaves to show green fluorescence; the autofluorescence of chloroplasts is red fluorescence; the combination of the two can localize and quantify the content of H2O2. It can be seen from the figure that the fluorescence content in the 200 mM NaCl treatment group is significantly greater than that in the watering control group, and the fluorescence content detected in the ice plant leaves treated with 100 mg / L of the nano-solution is less than that in the 200 mM NaCl treatment group, indicating that spraying 100 mg / L of MnPSe3 nano-solution under salt stress reduces the content of H2O2 in the leaves.

[0064] 8. Metabolism of Nanoparticles

[0065] The MnPSe3 nanomaterial was co-incubated with Dil dye to form Dil-MnPSe3. After applying Dil-MnPSe3 to the leaves, small round pieces with a diameter of 5 mm were taken at 0 h, 3 h, 6 h, 9 h, 12 h, and 24 h respectively, placed face up on a glass slide, and pressed.

[0066] The samples were imaged using a Leica SP8 laser confocal scanning microscope. The Dil dye can make the nano-MnPSe3 show green fluorescence; the chloroplasts show red autofluorescence; the combination of the two can show that with the extension of the material treatment time, the nano-MnPSe3 undergoes metabolism. The results are as Figure 7 shown. With the extension of time after spraying MnPSe3 on the leaves, the fluorescence content also gradually decreases, indicating that the nanoparticles may have degraded, diffused, or been absorbed by plant cells on the leaf surface, resulting in the weakening of the fluorescence signal, suggesting that the residual amount of MnPSe3 in the ice plant decreases with time, so there will be no pollution of the MnPSe3 nanomaterial in the ice plant.

[0067] 9. Detection of the contents of soluble sugar and soluble protein

[0068] The detection of the soluble sugar content of the samples used a soluble sugar content kit (Suzhou Grees Biological, soluble sugar content (SS) kit (G0501F)). Using the dehydration of sugars under the action of concentrated sulfuric acid to generate furfural or hydroxymethylfurfural, which reacts with anthrone to form a blue-green derivative, which has the maximum absorption at 620 nm, and the light absorption value is proportional to the sugar content. The detection of the soluble protein content of the samples used a BCA method protein content determination kit (Suzhou Grees Biological, protein content (SP) kit (G0418W)). The BCA method is to use the peptide bonds in proteins to reduce cupric ions to cuprous ions under alkaline conditions, and then form a purple-blue complex, which has the maximum absorption peak at a wavelength of 562 nm, and the color depth is proportional to the protein concentration, so as to determine the protein content by colorimetry.

[0069] Plants will increase the soluble sugar content under salt stress, which is used to maintain osmotic balance, protect cells from oxidative damage, provide energy, and regulate signal transduction; plants will increase the soluble protein content under salt stress, which is used to regulate osmotic balance, protect enzyme activity, signal transduction, protein synthesis and metabolism regulation, and maintain the stability of cell structure. These mechanisms can help plants survive and grow in a salt stress environment. From Figure 8 the figure, it can be seen that salt stress will increase the contents of soluble sugar and soluble protein, and using the nano-solution can restore them to normal levels. It can be seen that after spraying the nano-MnPSe3 solution, the contents of soluble sugar and soluble protein have no obvious difference from the control group, further confirming that nano-MnPSe3 can relieve the salt stress of the ice plant.

[0070] Example 2 Verification of the hypoglycemic and anti-aging functions of ice plants by spraying nano-MnPSe3 under salt stress

[0071] 1. Preparation of crude extracts of ice plants

[0072] The ice plants after different treatments in Example 1 were dried and then ground into powder. 10 g of the powder was taken and added to ethyl acetate or 70% ethanol at a ratio of w:v = 1:20. It was ultrasonically extracted at room temperature for 2 h, allowed to stand and filtered to remove the residue, and the filtrate was concentrated under reduced pressure to remove the organic solvent to obtain the crude extract. It was ultrasonically dissolved in a solution with a volume ratio of methanol to water of 9:1, and the lipid components were removed by extraction with petroleum ether. It was further concentrated under reduced pressure to obtain the crude extract, which was stored in a refrigerator at 4 °C for subsequent experiments.

[0073] 2. Detection of antioxidant activity

[0074] The antioxidant activity of the samples was detected by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) method. 3.5 mg of DPPH was taken and dissolved in absolute ethanol, transferred to a 10 mL volumetric flask, and the working solution was stored in the dark at 4 °C for later use. The ice plant samples were dissolved in methanol to a concentration of 10 mg / mL for later use. Using a 96-well plate, 200 μL of the above working solution + 50 μL of the crude extract were added to each well, and the absorbance was measured at 517 nm using an enzyme-linked immunosorbent assay (ELISA) reader for a total of 30 min, with measurements taken every 1 min. The control group used 200 μL of the working solution + 50 μL of methanol.

[0075] The results are as Figure 9 shown, Figure 9 and present the experimental results of the scavenging rate of DPPH free radicals by the crude extract of ice plant leaves. In this Example 2, ethyl acetate was used as the extraction reagent to compare the antioxidant activities of the crude extracts of ice plant leaves under different treatments. It can be seen from the figure that the ethyl acetate extraction method shows significant advantages in improving the scavenging rate of DPPH free radicals. The crude extract of ice plant leaves obtained by extraction with ethyl acetate can more effectively extract the antioxidant active components therein, significantly enhancing the ability to scavenge DPPH free radicals.

[0076] 3. Detection of α-amylase inhibitory activity

[0077] 20 μL of the sample to be tested (using DMSO as the solvent), 80 μL of sodium phosphate buffer (pH 6.0), and 0.125 U / mL α-amylase solution were added to a 96-well plate and mixed well. It was shaken for 2 min, incubated at 37 °C for 10 min, and then 20 μL of 10 mM CNP-G3 solution was added. The absorbance of the product was measured at 405 nm, the reaction time was 30 min, and the number of measurements was 11 times, with 10% DMSO used as the blank control.

[0078] The results are as Figure 10 shown, Figure 10The experimental results of the inhibition rate of the crude extract of Mesembryanthemum crystallinum L. leaves on α-amylase are presented. In this Example 2, 70% ethanol was used as the extraction reagent to compare the inhibition of the α-amylase activity by the extracts of Mesembryanthemum crystallinum L. leaves under different treatments. It can be seen from the figure that the 70% ethanol extraction method shows significant advantages in improving the inhibition rate of α-amylase. This indicates that 70% ethanol as the extraction reagent can more effectively extract the components with anti-amylase activity in Mesembryanthemum crystallinum L. leaves, thereby significantly enhancing its inhibitory effect on α-amylase.

[0079] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. Application of MnPSe3 nanoparticles in enhancing plant resistance to salt stress.

2. The application according to claim 1, characterized in that, The method of the application is as follows: Mix MnPSe3 nanoparticles evenly with water to prepare a nano-solution, and then spray the nano-solution on the surface of plant leaves.

3. The application according to claim 2, wherein The mass-volume ratio of the MnPSe3 nanoparticles to water is 50 - 150 mg / L.

4. The application according to claim 2, characterized in that, The interval time of spraying is 4 - 7 days, and the number of spraying times is 1 - 2 times.

5. The application according to claim 2, wherein The plant is Mesembryanthemum crystallinum.

6. Use of the MnPSe3 nanoparticles according to claim 1 in enhancing the antioxidant capacity of plants under salt stress, characterized in that, The application method is: dissolve the MnPSe3 nanoparticles to a concentration of 50 - 150 mg / L and then spray on the surface of plant leaves.

7. Use of the MnPSe3 nanoparticles according to claim 1 in enhancing the anti-glycation activity of plants under salt stress, characterized in that, The application method is: dissolve the MnPSe3 nanoparticles to a concentration of 50 - 150 mg / L and then spray on the surface of plant leaves.

Images